EP 0 922 797 A2 discloses a spin rotor for an open-end spinning machine, wherein, on the circumference thereof, an identification designation is placed. The identification marking is read, without physical touching, by a sensor, which is installed on an attendant service unit. The signal which contains an identification designation to be read off by the service unit, is compared with data in a control device. If the signal does not comply with a predetermined set of designation data, then the service unit is commanded to withhold a resumption of spinning on the concerned open-end spinning machine. In this way, assurance is provided that, for instance, only spin rotors which are without question technically appropriate can be brought into service. The proposed identification marking can be a bar code or a transponder. The sensor detects and reads the identification marking inductively or optically. The application of the identification marking is complex and requires a separate work step in the manufacture of a spin rotor.
EP 1 035 241 A1 makes known a spin rotor, wherein, on the circumference of the rotor plate, a designation is placed, which, upon stillstand of the spinning rotor, can be read visually by a service operator. In this way, however, no automatic control of the type of spin rotor can be realized.